The NIKA2 Sunyaev-Zeldovich Large Program: Sample and upcoming product public release

TL;DR

This paper presents the initial results of the NIKA2 SZ Large Program, including tSZ maps of 38 galaxy clusters, demonstrating the potential of combined tSZ and X-ray data for precise cluster mass measurements and setting the stage for future cosmological studies.

Contribution

It introduces a new high-resolution tSZ mapping pipeline and provides the first detailed tSZ maps for a significant sample of galaxy clusters, advancing cluster-based cosmology.

Findings

tSZ maps for 38 galaxy clusters at intermediate redshifts

Demonstrated combined tSZ and X-ray analysis for accurate mass estimates

Developed a standard data analysis pipeline for future data releases

Abstract

The NIKA2 camera operating at the IRAM 30 m telescope excels in high-angular resolution mapping of the thermal Sunyaev-Zeldovich effect towards galaxy clusters at intermediate and high-redshift. As part of the NIKA2 guaranteed time, the SZ Large Program (LPSZ) aims at tSZ-mapping a representative sample of SZ-selected galaxy clusters in the catalogues of the Planck satellite and of the Atacama Cosmology Telescope, and also observed in X-ray with XMM Newton or Chandra. Having completed observations in January 2023, we present tSZ maps of 38 clusters spanning the targeted mass ($3 < M_{500}/10^{14} M_{\odot} < 10$) and redshift ($0.5 < z < 0.9$) ranges. The first in depth studies of individual clusters highlight the potential of combining tSZ and X-ray observations at similar angular resolution for accurate mass measurements. These were milestones for the development of a standard data analysis pipeline to go from NIKA2 raw data to the thermodynamic properties of galaxy clusters for the upcoming LPSZ data release. Final products will include unprecedented measurements of the mean pressure profile and mass observable scaling relation using a distinctive SZ-selected sample, which will be key for ultimately improving the accuracy of cluster based cosmology.